Aquarium filter assembly

ABSTRACT

An aquarium filter having a housing unit which is adapted to be mounted onto a wall of an aquarium tank. The housing includes an inlet chamber for receiving contaminated water from the aquarium tank and a filter chamber for filtering the contaminated water from the inlet chamber. A motor unit is supported by the housing and includes stator laminations which can be energized by means of a coil. A removable unitary intake assembly is positioned in the housing. The intake assembly includes an intake tube for supplying the contaminated water from the aquarium tank to the inlet chamber. It also includes a rotor assembly having an impeller mounted on it. The rotor assembly extends into the intake storage chamber and is magnetically coupled to the stator laminations to thereby drive the impeller pump.

BACKGROUND OF THE INVENTION

This invention relates to aquarium filters, and more particularly to anexternal aquarium filter utilizing a magnetically coupled pump impellerand having an easily removable, unitary intake assembly.

Aquarium filters are regularly utilized for the purpose of aeration andfiltration of the aquarium water and at the same time providecirculation to such water. One type of aquarium filter is an externallymounted filter which houses filtration equipment and includes a pumpingmechanism which induces the circulation of water from the aquariumthrough the filtration equipment and then returns the clean water to theaquarium.

In order to provide circulation of the water, a suitably adapted pumpingmechanism must be provided within the water flow path. In some filters,a motor driving a pump is hermetically enclosed and positioned directlywithin the flow path. However, such pumping mechanisms are costly anddifficult to repair.

In other prior art devices the motor is maintained in a separatelocation from the flow path and is magnetically coupled to an impellerwhich is positioned in the flow path. One such prior art device isdescribed in U.S. Pat. No. 3,512,646. Another magnetically coupledaquarium filter is described in U.S. Pat. No. 4,093,547. In both thesedevices, the entire motor, including the stator and rotor are mountedexternally of the flow path and a separate impeller is magneticallycoupled to the rotor. However, it is difficult to gain access and cleanthe impeller.

One type of motor pump assembly which permits completely submergedoperation of the motor is described in U.S. Pat. No. 3,853,429. In thistype, again it is difficult to gain access to the parts of the motorassembly in order to provide cleaning and repair.

In the externally mounted aquarium filters, an intake mechanism must beprovided in order to supply the contaminated aquarium water to thefilter. This intake mechanism and impeller has a tendency of gettingclogged by bits of aquatic vegetation and other detritus thataccumulates in an aquarium. It is therefore of importance to be able toeasily remove the intake assembly and impeller assembly in order toclean it. In most cases, since the intake assembly is associated withthe impeller, the problem of cleaning the intake assembly is compoundedby the necessity to also remove the impeller which is virtuallyinaccessible without emptying and inverting the filter.

Maintenance of filtration devices requires replacement of the filteringmaterial and also requires regular cleaning of the intake assembly andespecially the impeller unit. With prior art filtration devices theintake assembly is often an integral part of the entire device and it istherefore necessary to remove and clean out the entire device in orderto remove any of the contamination particles clogging the flow path. Inaddition, in order to gain access to the impeller, it was necessary tosubstantially disassemble the entire device. Accordingly, cleaning,repairing and maintenance of prior and filtration devices presentedconsiderable problems.

SUMMARY OF THE INVENTION

It is accordingly an object of the present invention to provide anaquarium filter assembly which avoids the aforementioned problems ofprior art devices.

Still another object of the present invention is to provide an aquariumfilter having a unitary intake assembly including an inlet flowmechanism integrally supporting an impeller mechanism, and wherein theunitary intake assembly is easily removable for cleaning and repairpurposes.

Yet a further object of the present invention is to provide an aquariumfilter assembly having a motor stator externally mounted of the filterhousing and having a magnetically coupled rotor impeller containedwithin a unitary intake assembly supported by the filter housing.

Still a further object of the present invention is to provide anaquarium filter assembly having a pump rotor assembly mounted internallyof the water flow chamber as part of a unitary intake assembly, andmagnetically coupled to an externally mounted stator assembly.

A further object of the present invention is to provide an aquariumfilter assembly having an impeller mounted on a rotor assembly as partof a unitary intake assembly, and having the rotor assembly magneticallycoupled to an externally mounted stator assembly.

A further object of the present invention is to provide an aquariumfilter assembly having an intake receiving chamber in flow communicationwith a filter chamber which, in turn, is separated by filtering devicesfrom a clean water chamber, and including a removable unitary intakeassembly associated with the receiving chamber, and a spillwayassociated with the clean water chamber.

Briefly, in accordance with the present invention, there is provided anaquarium filter assembly having a housing unit which is adapted to bemounted externally on a wall of an aquarium tank. The housing unitcontains an inlet chamber for receiving contaminated water from theaquarium tank, and a filter chamber for filtering the contaminated waterpassing from the inlet chamber. The two chambers are in fluid flowcommunication with each other. A motor unit is provided which issupported by the housing unit. A removable unitary intake assembly issupportedly positioned in the housing and includes inlet flow tubes forsupplying the con-taminated water from the aquarium tank to the inletchamber, and a pump impeller unit which is magnetically coupled to themotor unit.

In an embodiment of the invention, the externally supported motor unitincludes stator laminations which define a bore therein. A tube dependsfrom the inlet chamber and fits into the bore. The pump impeller unit ismounted on a rotor and extends from the inlet flow tubes into thedepending tube to be magnetically coupled to the stator laminations.

These and other objects, features and advantages of the invention will,in part, be pointed out with particularity, and will, in part, becomeobvious from the following more detailed description of the invention,taken in conjunction with the accompanying drawings, which form anintegral part thereof.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings

FIG. 1 is a perspective view of the aquarium filter assembly inaccordance with the present invention;

FIG. 2 is an exploded perspective view of the aquarium filter assemblyshown in FIG. 1;

FIG. 3 is a cross sectional elevational view taken along line 3--3 ofFIG. 1, and specifically showing the intake assembly operativelyassociated with the housing unit, and the externally supported motor;

FIG. 4 is a cross sectional elevational view taken along line 4--4 ofFIG. 1 and specifically showing the filter chamber in communication withthe clean water chamber and the spillway;

FIG. 5 is a perspective view of the cover inverted, and showing thecover used to transport filter material being discarded;

FIG. 6 is an elevational view of the intake assembly specificallyshowing it as a unitary removable unit; and

FIG. 7 is a cross sectional view of the clutch mechanism between theimpeller and the rotor sleeve.

In the various figures of the drawing, like reference charactersdesignate like parts.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, there is shown an aquarium filterapparatus which is designated generally by the number 10 and comprises atank 12 in which is placed a sheet of filter material 14. A cover member16 is disposed over the tank 12. A motor housing 18 is retained beneaththe tank 12 by means of the U-shaped bale 20. A unitary intake assembly,as shown in FIG. 6 and designated generally by 22 is positioned in thetank 12.

More particularly, the tank 12, which is typically formed of transparentplastic material, includes a substantially rectangular configurationhaving a rear wall 24, opposing side walls 26, 28, and a front wall 30.Intermediary double walls 30,32 extend from the front wall 30 partiallytowards the rear wall 24. The tops of the intermediary walls 31, 32terminate at a point lower than the upper edge 34 of the rear wall 24.The intermediary walls 31, 32 separate the tank into an intake receivingchamber 36 on the other side of wall 31. A downwardly sloped wall 40 isspaced between the lower part of the intermediary walls 31, 32 and therear wall 24, and extends only the partial height of the rear wall 24.The sloped wall 40 also terminates at a point below the upper edge ofthe front wall 30. This permits the fluid in the intake chamber 36 whichis at a level above the water to flow over the wall 40 and into thefiltering chamber 38.

The filtering chamber 38, is also divided by means of the filter 14inserted in the filtering chamber. Specifically, as best seen in FIGS.1, 2 and 4, a filter 14 is formed of a frame 42 supporting filtermaterial 44 contained between a front and rear wall 46, 48. The frame 42is maintained in place by means of a vertical groove 50 located alongside wall 28 and a corresponding vertical groove 52 located in theintermediary wall 31. These grooves permit sliding down of the frame 42into the filtering chamber 38 where it is maintained in place.

The compartment formed between the rear wall 24 and the filter 14 ishereinafter referred to as the filtering chamber 54. The compartmentformed forward of the filter 14 and until the front wall 30, defines aclean water compartment 56. It should be noted that the filter 14substantially fills the entire height of the tank 10. The upper end ofthe front wall 30 terminates in a downwardly directed, arcuately shapedforward wall 58 which forms a spillway for water flowing from the cleanwater compartment 56 back into the aquarium tank. A substantiallyhorizontal ledge 60 is interposed between the spillway 58 and thevertical front wall section 30. Another forward lip portion 62 is formedat the front end of the spillway 58. The height of the spillway 58 isabove the height of the wall 40, as can best be seen in FIG. 3.

The cover 16 is arcuately shaped to conform to the arcuate shape at thetop of the tank 12. The cover 16 includes an arcuate upper surface 64with a downwardly depending rear skirt portion 66 and side skirtportions 68, 70. A semicircular protruding bulge 72 is formedproximately the distal end of the arcuate cover surface 64 and on oneside thereof, to accommodate the intake tube assembly, which will behereinafter described.

A ledge 74, arcuately shaped to conform to the shape of the skirtportion 70, is formed along the upper end of the wall 28 of the filtertank 12. A corresponding arcuate ledge 76 is also formed inwardly of theside wall 26. At the rear edge of the ledge 74, there is provided a rampsurface 78 which terminates in the verticle wall 80. A correspondingramp surface 82 is formed at the rear of the ledge 76 and alsoterminates in a vertical wall 84. A downwardly directed stop member 86is provided along the skirt portion 70, and a corresponding stop member88 is provided at the rear of the skirt portion 68.

Accordingly, the upper cover will snugly fit on top of the tank byhaving the skirt 70 sit on the ledge 74 with the stop member 86 abuttingthe vertical wall 80 at the end of the ramp surface 78. Correspondingly,on the other side, skirt 68 will sit within the ledge 76 and the stopmember 88 will abut the rear of the ramp section 82. This will hold thecover securely in place and at the same time will retain itsubstantially flush with the upper edges of the rear wall 34.

As can best be seen in FIGS. 1 and 3, the lower edge 90 of the cover 16terminates in a common vertical plane but spaced above the lower lip 62to define an opening 92 through which the clean water can pass as itflows along the spillway 58 and from there returns to the aquarium.

It is noted that the cover is removable and can act as a tray forremoval of clogged filter cartridge. Specifically, in order to clean,the filter material 14 can be slid out of its position in the filter andtemporarily placed on the inverted cover. The cover will then serve as atray holding the used filter material until its disposal at a suitabledisposal unit.

A forward facing surface 96 interconnects the front of intermediarywalls 31, 32 at the front of the filter. At the front of the intakereceiving chamber 36 there is provided a forward wall having a verticalsection 98 which continues downwardly into a forward arcuately slopingsection 100. The forward section 100 corresponds in curvature to thearcuate shape of the spillway 58. A substantially horizontal ledge 102interposes the front wall 30 with the arcuate section 100. A forward lip104 terminates the front end of the arcuate section 100.

A semicircular groove 106 is formed into the lip 104 and thecorresponding arcuate section 100 to accommodate the intake tubeassembly, as will hereinafter be described. The position of thesemicircular groove 106 corresponds to the bulge 72 formed in the cover16 so that the intake tube assembly is accommodated therebetween.

The upper end of the vertical wall section 98 at the front of the intakereceiving chamber 36 has a substantially U-shaped groove 108 formedtherein and a channel 110 is formed in that U-shaped groove. The channel110 will receive a supporting member of the intake tube assembly inorder to support it in position, as will hereinafter be described.

At the bottom of the receiving chamber 36 there is formed a base wall112 from which depends a tube 114 having a funnel shaped upper end 116and a lower conical tip 118. A downwardly depending peripheral skirtportion 120 is formed about the lower wall 112 of the receiving chamber36.

Adjacent the side wall 26 of the receiving chamber 36 is provided anupstanding support member 122 having a bifurcated V-shaped receivingnotch 124. In the lower wall 112, and spaced from the depending tube114, there is provided a hollow cylindrical tunnel 126 defining acircular opening 128 passing therethrough. The opening 128 is accessibleexteriorly from either side of the base wall 112.

The bail portion 20 comprises a substantially U-shaped member includingthe legs 130, 132 interconnected by the bight portion 134. At the distalends of the legs 130, 132 there are provided the enlarged heads 135, 136from which inwardly extend the pins 138, 140. The pins 138, 140 aresized to fit within the opening 128 to permit the bail 20 to dependbeneath the intake receiving chamber 36.

The motor housing 18 comprises a plastic housing member 142 with acorresponding cover 144. Within the housing 142 there is contained amotor of a standard type, and including a plurality of statorlaminations 146 defining a bore 148 therethrough and accommodating awinding 150 from which extends the wire 152 for energizing the winding.The cover 144 has an opening coaxial with the bore 148 formed in thestator laminations 146. The cover 144 can be held in place by means offasteners such as a rivet, screw etc. inserted in the openings 154 whichcan also serve to hold the stack of laminations secured in place. Inaddition rivet 155 can hold the housing sections in place.

A rudder 156 extends vertically downward from the motor housing 142 andincludes a notch 158 therein which can accommodate the bight portion 134of the bail 20. A rib 160 is formed internally and externally of thebale 20 to accurately be positioned in the notch 158 in the rudder 156.

It should be appreciated that the motor housing 18 can be positionedbeneath the intake receiving chamber 36 by inserting the depending tube114 into the aperture provided in the motor housing and extending thetube 114 into the bore 148 in the stator laminations. The motor housing142 can then be held in place by passing the bail 20 around the outsideof the motor housing so that the rib 160 of the bight portion 134 isreceived within the notch 158 of the rudder 156. This will retain themotor housing removably secured beneath the bottom wall 112.

The motor housing 142 can be protected by means of the skirt 120 whichsurrounds the upper portion of the motor housing. Also, an upwardlyextending peripheral wall 162 can be provided about the upper portion ofthe motor housing 142 which will closely abut the funnel 116 of thedepending tube 114.

The removable intake assembly is shown formed as a unitary assembly, asshown in FIG. 6. The intake assembly shown generally at 22 comprises asubstantially U-shaped intake flow tube 166 including a first verticalleg 168 and a second vertical leg 170 interconnected by a connecting leg172. The three legs are in fluid flow communication. The connecting leg172 is downwardly angled and the leg 168 terminates at its lower end ata level lower than the termination of the leg 170.

The upper distal end 174 of the leg 172 extends beyond itsinterconnection to the leg 170. A plug 176 including a cap 178 is usedto rotate a valve plug 180 into the end 174 of the connecting leg 172.The valve plug 180 has an arcuately shaped termination 182 which can berotatably positioned at the junction between the vertical leg 170 andthe connecting leg 172 in order to serve to control the opening at thejunction to thereby limit the flow of water through the U-shaped intaketube 166. O-ring 184 can be positioned about the cap 178 to provide atight fit into the opening.

The lower end of the leg 168 terminates in a wider neck portion 186. Asshown in FIG. 3, the upper part of the neck portion 186 has a thinnerwall section 188 than its lower portion 189 to thereby define a shoulder190 therebetween.

As best shown in FIG. 2, an extension tube 192 can be inserted into theneck 186. The extension tube 192 includes a cylindrical body portion 194with upwardly extending arms 196, 198. Each of the arms includesoutwardly directed fingers 200. The arms 196, 198 can be inserted intothe neck portion 186 with the fingers 200 catching onto the shoulder 190in order to retain the extension tube 192 in place. The lower end of thearms 196, 198 include an outwardly directed flange 202 which serves as astop for the neck portion 186. At the lower end of the extension tube192 there is provided a terminating end 204.

Alternately, a strainer 206 can be inserted into the neck 186. Againarms 208, 210 are provided with outwardly directed fingers 212 on thearms 208, 210 in order to permit catching onto the shoulder 190 in theneck portion 186. The strainer 206 has a hollow cylindrical body member214 with a plurality of spaced apart openings 216 which can serve tofilter the contaminated water entering into the intake tube 166.

About the periphery of the inter-connecting leg 172, there is provided aU-shaped flange 218 with a substantially flattened top edge 220. Theperiphery of the flange 218 terminates in a knife edge. At the lower endof the leg 170, there is provided an outwardly flared section 222 whichterminates in a collar 224. A laterally extending positioning tab 226extends from the collar. Also, a plurality of openings 228 are formedabout the periphery of the collar for receiving the rotor assembly, tobe hereinafter described.

The rotor assembly, as best seen in FIG. 2, includes a shaft 230 havingupper and lower axially extending tips 232, 234. A mounting plug 236 isfirmly mounted onto an upper end of the shaft 230. The mounting plug 236includes a square shaped body 238 having an aperture 239 with a circularperipheral flange 240. Firmly positioned on the plug 236 is a mountingring 242. The mounting ring 242 includes a circular hub 244 having asquare shaped central opening 246 which sits on the square shaped plug238. An outer circular ring 248 is retained by the hub 244 by means ofthe spokes 250. In this way, fluid can pass between the hub 244 and theperipheral ring 248. Outwardly extending tabs 252 extend from themounting ring 248 and are retained within the openings 228 on the collar224. The mounting ring 242 is held in place on the shaft 230 by means ofthe push on retaining washer 254.

In this manner, the mounting ring 242 is securely fixed onto the shaft230 and is supported by the collar 222 of the intake tube 166.Furthermore, because it is securely held on the shaft 230, the mountingring 242 also holds the shaft 230 in fixed position.

A magnet holder 256 is positioned centrally along the shaft 230. Themagnet holder 256 is formed of non-conductive material, such as plastic.It forms a sleeve which can rotate about the shaft 230. The magnetholder 256 comprises a substantially cylindrical body portion 258terminating in a peripheral flange 260. At the bottom of the flange 260there is provided a substantially square shaped leg portion 262. At theupper end of the body portion 258, there is provided a reduced diametercylindrical neck portion 264 including an outwardly directed finger 266which forms part of a clutch mechanism for engaging an impeller, to behereinafter described.

A magnet 268, typically of ferrite material, is substantiallycylindrical in shape and includes a square opening therethrough 270which corresponds in shape to the square leg portion 262 of the magnetholder 256. The magnet 268 can be molded onto or positioned onto thesquare shaped leg portion 262 so as to be firmly supported thereby. Thecircular flange 272 at the lower end of the leg portion 262 serves tohold the magnet 268 in place.

Positioned above the magnet holder 256 is provided an impeller 274. Theimpeller 274 comprises a circular base 276 with an upstanding centralcircular hub 278. Laterally extending fins 280 extend from the hub 278and are positioned on the base 276.

A shaft bearing 282 is pressed downwardly into a central opening withinthe hub 278. The shaft bearing 282 includes a cylindrical body portion284 with an upper flange 286 which sits above the hub 278.

As can best be seen in FIGS. 3 and 7, the shaft bearing 282 fitsinternally of the neck portion 264 of the magnet holder 256 as well asthe impeller hub 278. The impeller hub fits about the neck portion 264.Downwardly depending from the lower surface of the base 276 of theimpeller 274, is a tab 288 which is positioned to engage the outwardlyextending finger 266 extending from the neck 264. As is best seen inFIG. 6, the tab and finger sections 288, 266 are positioned so as tomatingly engage. As the magnet holder 256 is caused to rotate, it willinitially begin rotating without the impeller moving. After at least aportion of a single rotation, the finger 266 will engage the tab 288 onthe impeller to thereby cause the impeller to rotate along with themagnet holder 256.

Accordingly, a clutch mechanism is provided between the impeller 274 andthe magnet holder 256. The holder 256 will therefore be permitted toinitiate rotation without the extra load of the impeller. In thismanner, less initial force is required in order to overcome the inertiaof the magnet holder 256 since the impeller is not impeding itsrotation. Only after initial inertia is overcome, and the magnet holder256 begins rotating, the clutch mechanism is engaged whereby theimpeller is driven by the rotation of the magnet holder 256.

Above the shaft bearing 282, there is provided a floating washer 290.The lower end of the shaft passes through a flexible bushing 292, suchas is formed of rubber. The center of the bushing 292 has a squarecutout 294 which receives a mounting plug 296. The mounting plug 296includes a substantially square body portion 298 with an upper circularflange 300. The opening 302 in the plug 296 tightly fits onto the shaft230 and the bushing 292 fits onto the square body portion 298 of theplug. A push-on retaining washer 304 secures the bushing 292 in place atthe lower end of the shaft. A floating washer 306 fits between the lowerbushing 292 and the magnet holder 256.

With the rotor assembled, it is inserted with the rubber mounting ring242 positioned within the collar portion 224 at the lower end of theintake tube 166. The rotor assembly will therefore axially depend fromthe leg 170.

The unitary intake assembly 22, as shown in FIG. 6, can be positionedinto the intake receiving chamber 36. The U-shaped flange 218 sitswithin the seat portion 110 in the front wall 98 of the intake receivingchamber 36 which serves to hold the unitary intake assembly in place.The tab 226 laterally extending from collar 224 fits within thebifurcated V-shaped notch 124 provided at the side of the receivingchamber 36 and accurately positions the unitary intake assembly inplace.

With the unitary intake assembly 22 suitably positioned, the rotorassembly will fit snugly into the depending tube 114. As can best beseen in FIG. 3, the lower bushing 292 will then snugly fit into thebottom of the depending tube 114 and will hold the shaft 230 in place.The shaft 230 will thereby be fixedly secured between the lower bushing292 and the upper mounting ring 242. However, the magnet holder 256 isfree to rotate about the shaft 230.

It should be appreciated, that in addition to providing free rotationalmovement of the magnet holder 256 about the shaft 230, there is alsoprovided axial play in the movement of the magnet holder 256.Specifically, there is movement of the holder axially along the shaftbetween the two floating washers 290 and 306. These washers, in turn,are limited in their axial movement by means of the upper fixed mountingplug 236 and the lower mounting plug 296. With the rotor assemblypositioned within the depending tube 170 as is best seen in FIG. 3, whenthe stator laminations 146 are energized by means of the coil 150, theywill create a magnetic flux. With the magnet 268 mounted on the magnetholder 256 and permitted to axially float, the magnet will suitablyorient itself in order to maximally cut the flux lines. Furthermore, itwill thereby cause the magnet holder 256 to rotate by means of themagnetic coupling between the magnet 268 and the stator laminations.Rotation of the magnet causes the magnet holder 256 to rotate, which inturn causes the impeller 274 to rotate.

It should be appreciated that the motor housing 18 does not include anyrotating parts. Only the stator fixed laminations are provided and acoil. All the rotating parts are provided directly within the intakereceiving chamber and the impeller as well as the rotor are bothprovided within the intake storage chamber.

The operation of the filter is as follows. The intake assembly, as shownin FIG. 6, is assembled with the rotor assembly axially extending fromthe lower end of the intake tube. The entire assembly as shown in FIG. 6is then inserted into the filter and accurately positioned by means ofthe U-shaped notch 110 and the bifurcated notch 124.

With the intake assembly accurately positioned, the rotor assembly willbe situated within the depending tube 114. This in turn will fit withinthe bore 148 of the stator laminations of the motor housing 18 heldbeneath the intake receiving chamber by means of the bail 20.

The filter is then positioned over the upper edge of an aquarium withthe ledge 60 of the spillway 58, as well as the ledge portion 102 of theintake support, serving to retain the filter in place at the upper edgeof the aquarium tank.

With the filter properly positioned, the intake downwardly extending leg168 should reach into the aquarium water. If necessary, the extensiontube 192 can be connected in order to reach the aquarium water. The coilof the motor is then energized by connecting it to a source of energy.This will then energize the stator and cause the rotor to turn about theshaft. This in turn will cause the impeller 274 to begin pumping. Itshould be noted, that when assembled, the impeller is positioned justbeneath the outlet mouth of the intake tube. As a result, thecontaminated water which is drawn up through the vertical leg 168 andpasses through the connecting leg 172 downwardly flows through thedepending leg 170 and is pumped into the receiving chamber by means ofthe impeller.

As the water accumulates in the receiving chamber 36, it reaches a levelsufficient to flow over the wall 40 and thereby passes into thefiltering chamber 38. Continuous pumping of the water into this chamberforces the water through the filter 14. The water will therefore passinto the clean water chamber 56. When the water reaches the edge of thespillway, it will pass over the spillway wall and flow back into theaquarium.

Since the entire intake assembly is formed of a unitary construction,when it is desired to clean or disconnect the filter, it is onlynecessary to lift off the cover 16 and immediately pull up the unitaryintake assembly. The entire intake assembly can thereby be removed,including both the intake tube as well as the rotor assembly, which isthen pulled out of the depending tube 114. This will permit cleaning theimpeller, as well as cleaning of the rotor and other moving parts. Itwill also permit cleaning of the intake tube from all material that mayhave collected therein.

It should further be appreciated, that the rotor assembly itself, canalso be separated from the intake tube simply by pressing on themounting ring 242. This will remove the tabs 252 from the slots 228 inthe collar 224 and the entire rotor assembly can then be separated forfurther cleaning.

The housing itself is provided with a peripheral stiffening member 307and also with short legs 308 on which the housing can stand. Thispermits storage of the filter by itself when it is not in use.

There has been described heretofore the best embodiments of theinvention presently contemplated. However, it is to be understood thatvarious changes and modifications may be made thereto without departingfrom the spirit of the invention.

I claim:
 1. An aquarium filter assembly, comprising:a housing unitadapted to be mounted on a wall of an aquarium tank, and comprising aninlet chamber for receiving contaminated water from the aquarium tank, afilter chamber for filtering the contaminated water, said chambers beingin fluid flow communication with each other, and means for introducingthe filtered water back into the aquarium tank; a motor unit supportedby said housing unit, and a removable unitary assembly supportablypositioned by said housing and comprising an intake tube having an inletend for insertion into the aquarium tank and a discharge end positionedin said inlet chamber thereby supplying the contaminated water from theaquarium tank to the inlet chamber, and a pump impeller unit dependingfrom a position proximate said discharge end and comprising a fixedshaft, a magnet rotatably mounted on said shaft for positioning inmagnetic flux relationship with said motor unit, and an impellerrotatable on said shaft and operably driven by said magnet therebypumping the contaminated water through the filter assembly, and whereinsaid unitary assembly of said intake tube and pump impeller unit isremovable as a single unit from said housing unit.
 2. An aquarium filterassembly as in claim 1, wherein said housing unit comprises a dependingtube, said motor unit comprises stator laminations defining a bore forreceiving said depending tube, and wherein said pump impeller unit isremovably received in said depending tube.
 3. An aquarium filterassembly as in claim 2, and comprising clutch means interposed betweensaid sleeve and said impeller to cause engagement therebetweensubsequent to initiation of rotational movement of said sleeve.
 4. Anaquarium filter assembly as in claim 2, wherein said sleeve is axiallymovable along said shaft within pre-fixed limits to thereby permitmagnetic positioning of said magnet within said laminations, and toreduce friction during rotation of said sleeve.
 5. An aquarium filterassembly as in claim 4, and further providing a lower bushing assemblyfor supporting said pump impeller unit in said depending tube and forlimiting the lower axial movement of said sleeve on said shaft, and anupper retaining assembly for removably depending said pump impeller unitfrom said intake tube.
 6. An aquarium filter assembly as in claim 5,wherein said intake tube comprises a substantially inverted U-shapedconfiguration, and wherein said tube depends from said inlet chamber. 7.An aquarium filter assembly as in claim 6, wherein the inlet end extendsto a lower level than the discharge end and an angularly upwardlyincluded connecting tube between the inlet tube and the discharge tube.8. An aquarium filter assembly as in claim 6, and comprising a pair ofpositioning members in said housing for positioning and supporting atleast two sections of said intake tube to thereby accurately positionsaid unitary assembly within said housing.
 9. An aquarium filterassembly as in claim 8, wherein said positioning members position aportion of said intake tube including said inlet end in forwardoverhanging relationship with respect to said housing unit.
 10. Anaquarium filter assembly as in claim 6, and comprising a motor housingcontaining said motor unit, and support means on said housing forremovably supporting said motor housing beneath the inlet chamber ofsaid housing unit.
 11. An aquarium filter assembly as in claim 10,wherein said support means comprises a pivotal bale depending from saidhousing unit, and a groove in said motor housing for receiving the bightportion of said bail.
 12. An aquarium filter assembly as in claim 6, andcomprising a control valve positioned between the connecting tubesection and the downwardly directed tube section of said intake tube,for controlling the flow of water into said filter assembly.
 13. Anaquarium filter assembly as in claim 1, comprising a removable verticalfilter means in said filter chamber for defining a clean watercompartment forward thereof, a spillway extending forward from the frontof said housing and communicating with said clean water compartment forproviding return of the clean water to the aquarium tank, said intaketube having an inlet end, support means for supporting said inlet endforward of said housing, and hook means defined under said spillway andunder said support means for overhanging an upper rim of the aquariumtank.
 14. An aquarium filter assembly as in claim 13, and comprising aremovable cover member for covering said housing unit and definingtogether with said housing unit and said filter means, a closedcompartment for said filter chamber.
 15. An aquarium filter assembly asin claim 13, and comprising a wall member between said inlet chamber andsaid filter chamber, the upper end of said separation wall terminatingat a higher level than said spillway.
 16. An aquarium filter,comprising:a filter housing for exteriorly overhanging onto a side edgeof an aquarium tank, and containing an intake receiving chamber forreceiving contaminated water from the aquarium tank, a filter chamberfor filtering the received water, a tube depending from said intakereceiving chamber and means for introducing the filtered water back intosaid aquarium tank; a motor housing unit dependedly supported from saidfilter housing beneath the intake receiving chamber exteriorly of thetank, and including a housing opening for receiving said depending tube;a pump means comprising a motor having its stator portion contained insaid housing unit and including stator laminations defining a borecoaxial with said housing opening, and its rotor portion positioned insaid depending tube and magnetically coupled to said stator portion;impeller means positioned in said intake receiving chamber and operatedby said rotor portion; a removable intake tube located forwardly of saidfilter housing and terminating into said intake chamber for supplyingthe contaminated water from the aquarium tank to the intake receivingchamber, and coupling means for depending said shaft axially from saidtermination of said intake tube, whereby said impeller is locatedproximate the termination of said intake tube, wherein said intake tubeand said rotor portion form a removable unitary assembly.
 17. Anaquarium filter as in claim 16, wherein said rotor portion comprises afixed shaft, a sleeve rotatable on said shaft, a magnet mounted on saidshaft and oriented to be in flux relationship with said laminations, andwherein said impeller is rotatably mounted on said shaft and driven bysaid sleeve.
 18. An aquarium filter as in claim 17, and comprisingremovable cover means on said filter housing, said unitary assemblybeing removably accessible upon removal of said cover means.